JP2004529759A - Process for selective hydrogenation of alkynes and catalyst therefor - Google Patents

Abstract

Acetylene-type compounds in olefin streams such as mixed 1,3-butadiene were selectively hydrogenated over supported copper catalysts on highly porous support surfaces such as alumina, silica and the like. Preferred carriers have an average pore diameter of greater than about 200 Angstroms, no micropores, a total pore volume of greater than about 0.65 cc / g, and a BET of preferably less than about 230 m ² / g. Has surface area. The copper catalyst is promoted, preferably with a Group VIII metal such as palladium, to improve the low activity of the copper catalyst. The product stream typically contains less than 20 ppm of total alkynes. The copper catalyst and the palladium promoted copper catalyst may also be adjusted with zinc oxide to improve the performance of the catalyst. Two or more copper catalysts promoted with different levels of palladium were charged to the reactor. Also preferably, the copper catalyst is adjusted with silver, gold or both silver and gold to reduce polymer formation by the copper component of the catalyst and improve the yield of olefins such as 1,3-butadiene. Prevents the loss of copper and / or palladium by leaching into the liquid phase of hydrocarbons.

Description

【００３９】
【表２】

【００４０】
実施例６
実施例５において使用したアルミナを、７００℃で３時間、空気中でか焼した。銅触媒を、このか焼したアルミナを使用して製造した。１２８mlの脱イオン水中の３０gのＣｕ（ＮＯ₃）₂．２．５Ｈ₂Ｏ、Ｎｉ（ＮＯ₃）₂．６Ｈ₂Ｏ、０．０４７gのＡｇＮＯ₃、０．３９６gのＣｒ（ＮＯ₃）₃．９Ｈ₂Ｏ及び０．３９６gのＣｏ（ＮＯ₃）₂．６Ｈ₂Ｏの溶液を作製した。ロータリーエバポレーターを使用して、７０gのアルミナに上記の溶液を含浸させた。含浸生成物を、１１０℃、真空オーブン中で一晩さらに乾燥した後に、４００℃、マッフル炉中で３時間、空気中でか焼した。触媒のＡＢＤは、０．５７g/ccだった。１８gのこの触媒を、１００mlの直径３mmのガラス球とブレンドし、対照実施例１におけるものと同じ反応器中に装填した。対照実施例１におけるものと同一の方法で、触媒を活性化した。
【００４１】
４４４重量ppmのメチルアセチレン、８２５重量ppmのビニルアセチレン及び６３４重量ppmのエチルアセチレン、５５．３６重量％の１，３−ブタジエン、０．１２重量％の１，２−ブタジエン、６．３９重量％のｔ−２−ブテン、４．１３重量％のｃ−２−ブテン、１６．８４重量％の１−ブテン、１２．３８重量％のイソブテン、３．５３重量％のｎ−ブタン、０．９７重量％のイソブタン、並びに０．０９重量％の他のもので構成される混合Ｃ₄流れを選択的に水素化して、アセチレン型不純物を１１９psigで除去した。この実施例においては、炭化水素及び水素速度を、炭化水素の場合に３cc／分、水素の場合に２７scc／分の一定速度で維持した。実施例６及び対照実施例１における銅触媒の試験結果を、実施例５から得られた結果と共に図４及び５に示す。
【００４２】
図４及び５は、本発明において開示する銅触媒の、従来技術に勝る優れた性能を明確に証明する。
【００４３】
実施例７
この実施例においては、接触蒸留塔を、混合Ｃ₄流れ中のアセチレン型不純物の選択的水素化のために使用する。より大きなバッチの触媒を、実施例５において説明したものと正確に同じ方法で、２４０グラムのアルミナを使用して製造した。触媒（９９．８８グラム）を、接触蒸留塔（直径１インチ×高さ２５フィート）中に装填した。塔中の触媒床の高さは、６フィートだった。触媒床の頂部及び底部の８０インチに１／４インチの鞍状物を充填した。対照実施例１において説明したものと同じ方法で、ただしガスの流量を触媒重量を基準として比例させて増大させて、触媒を活性化した。
【００４４】
実施例６において使用したものと同じ供給物中のアセチレン型不純物を、接触蒸留態様で選択的水素化を実行することで除去した。炭化水素供給速度は、１．２ポンド／時だった。水素速度はランの初めに１scf／時だったが、ランの最中により高い速度に変更された。炭化水素及び水素供給物を、鞍状物充填材よりも下の箇所において供給した。結果を図６に示す。３scf／時以上の水素速度で、供給物中のエチルアセチレン及びビニルアセチレンは事実上全て除去された。１，３−ブタジエンのほぼ完全な回収が得られた。図６に示すように、触媒は、固定床稼働よりも接触稼働態様下ではるかに安定だった。
【００４５】
実施例８
本発明において開示する銅触媒中に銅触媒の性能を改良するために酸化亜鉛を取り入れることの有益な効果を証明するために、この実験を実行した。銅触媒を、実施例５において使用したものと同一の手順に従って製造した。１００mlの脱イオン水中の２２．６gのＣｕ（ＮＯ₃）₂．２．５Ｈ₂Ｏ、Ｎｉ（ＮＯ₃）₂．６Ｈ₂Ｏ、０．０４gのＡｇＮＯ₃、及び４．０gのＺｎ（ＮＯ₃）₂．６Ｈ₂Ｏの混合溶液を作製した。ロータリーエバポレーターを使用して、実施例５において使用したものと同じ６０gのアルミナに上記の溶液を含浸させた。含浸生成物を、１１０℃、真空オーブン中で一晩さらに乾燥した後に、４００℃、マッフル炉中で３時間か焼した。１８gのこの触媒を、１００mlの直径３mmのガラス球とブレンドし、対照実施例１において使用したものと同じ反応器中に装填した。触媒活性化を、対照実施例１において説明したものと同じ方法で実行した。
【００４６】
４７５ppmのメチルアセチレン、９５９重量ppmのビニルアセチレン及び７３１重量ppmのエチルアセチレン、５４．８７重量％の１，３−ブタジエン、０．１２重量％の１，２−ブタジエン、６．４２重量％のｔ−２−ブテン、４．１６重量％のｃ−２−ブテン、１６．７６重量％の１−ブテン、１２．５３重量％のイソブテン、３．５６重量％のｎ−ブタン、１．２７重量％のイソブタン、並びに０．０９重量％の他のもので構成される混合Ｃ₄流れを選択的に水素化して、その中のアセチレン型不純物を除去した。選択的水素化を、１４７°Fの一定温度及び１１９psigで実行した。一定の炭化水素及び水素供給速度である３ml／分（６．１ＷＨＳＶ）及び２７．１scc／分をランの間中使用した。このランの結果を、図７及び８に要約する。銅触媒中に取り入れられた酸化亜鉛が触媒性能に及ぼす有益な効果が、この実施例において明確に証明される。
【００４７】
実施例９
この実施例においては、本発明において開示する好ましい溶媒のうちの１つであるテトラヒドロフラン（ＴＨＦ）の有用性を証明する。実施例５において製造した銅触媒（３６グラム）を、対照実施例１において使用したものと同じ反応器中に装填した。この実施例において使用する混合Ｃ₄供給物は、以下の組成を有した；２０ppmのメチルアセチレン、５８８ppmのビニルアセチレン、５９９ppmのエチルアセチレン、４４．５１重量％の１，３−ブタジエン、０．０７重量％の１，２−ブタジエン、６．２９重量％のｔ−２−ブテン、４．３３重量％のｃ−２−ブテン、１５．９７重量％の１−ブテン、１８．０４重量％のイソブテン、９．３６重量％のｎ−ブタン、１．３０重量％のイソブタン、並びに０．０１重量％の他のものである。１７６時間の運転時間の後、反応器を、Ｎ₂ガスを用いてフラッシングした後に、１４７°F、２００psigで１時間、次に１５７°Fで５時間、１０cc／分のＴＨＦ、６６．９scc／分のＨ₂で、触媒を、ＴＨＦを用いて洗浄して、触媒表面に堆積したポリマーを除去した。反応器を、Ｎ₂ガスを用いてフラッシングした後に、選択的な水素を継続した。一定温度（１４７°F）及び圧力（１１９psig）をランの間中維持した。この実験の最中のランの条件を表３に列記する。
【００４８】
この実験の結果を、図９に示す。図９に示すように、アセチレン型不純物の漏出が１２８時間の運転時間で起きた。しかし、触媒をＴＨＦを用いて洗浄した後に、漏出の場合と同じ条件下で得られた生成物は、検出可能な量のアセチレン型不純物を含まなかった。
【００４９】
【表３】

【００５０】
従って、ＴＨＦは、触媒再生のための好ましい溶媒のうちの１つである。またＴＨＦは、接触蒸留塔を使用して選択的水素化を実行するために使用される好ましい溶媒のうちの１つである。ＴＨＦをＣＤ選択的水素化において溶媒として使用する場合に、ＴＨＦを触媒床よりも上で蒸留塔に供給することができ、またはこれを混合Ｃ₄供給物流れと共に塔に供給することができる。こうした２つの場合には、塔稼働のための異なる条件が必要となろう。後者の場合、塔は、ＴＨＦに関して全内部還流（total internal reflux）条件下で稼働しよう。両方の場合に、ＴＨＦはボトム生成物として塔から除去され、塔に再循環されよう。しかしながら、再循環ＴＨＦ流れの一部は、再循環流れ中の重質成分の蓄積を避けるために、塔に戻る前に分離器中で精製されよう。
【００５１】
実施例１０Ａ
対照実施例２において使用した混合Ｃ₄供給物中のアセチレン型不純物（７１３２ppmの全アセチレン類）の選択的水素化に関して、実施例５において製造した銅触媒を試験した。１８gの触媒を、１００mlの直径３mmのガラス球とブレンドし、対照実施例１におけるものと同じ反応器中に装填した。対照実施例１におけるものと同一の方法で、触媒を活性化した。選択的水素化を、１４７°Fの一定温度及び１１９psigで実行した。最初の６６．５時間の運転時間の間、炭化水素及び水素供給速度は、それぞれ２．９ml／分（５．８７ＷＨＳＶ）及び４５scc／分であり、次に、それぞれ１．４ml／分（２．８３ＷＨＳＶ）及び２４．１scc／分に変更された。
【００５２】
実施例１０Ｂ
パラジウムを用いて促進された銅触媒を、本発明に従って製造した。実施例５において使用したアルミナを、９００℃で３時間、空気中でか焼した。１１０mlの脱イオン水中に２８．７gのＣｕ（ＮＯ₃）₂．２．５Ｈ₂Ｏ、Ｎｉ（ＮＯ₃）₂．６Ｈ₂Ｏ、０．０４gのＡｇＮＯ₃、０．３４gのＣｒ（ＮＯ₃）₃．９Ｈ₂Ｏ及び０．３４gのＣｏ（ＮＯ₃）₂．６Ｈ₂Ｏを溶解させることで、混合溶液を作製した。ロータリーエバポレーターを使用して、上記のか焼したアルミナ（６０g）にこの溶液を含浸させた。含浸生成物を、１１０℃、真空オーブン中で一晩さらに乾燥した後に、これを、４００℃、マッフル炉中で３時間、空気中でか焼した。５．４６９グラムの水性硝酸パラジウム（ＩＩ）溶液（オールドリッチ ３８，００４−０（Aldrich 38,004-0）；１０重量％の硝酸中の１０重量％のＰｄ（ＮＯ₃）₂）を、アトマイザーを使用して銅触媒球（２９．７６２グラム）表面に噴霧し、その間、銅触媒球は平坦な表面上をあちらこちらに転がり回って、球はパラジウム溶液で一様にコーティングされた。パラジウム塩溶液の微細なミストを生成することが非常に重要である。パラジウム溶液噴霧済みの生成物を、２５０℃で２時間、空気中でか焼した。Ｃｕ／Ｐｄ触媒のＡＢＤは、０．５２g/ccだった。この触媒の分析は、８．２０％のＣｕ、０．７１％のＰｄ、０．２０％のＮｉ、０．１１％のＣｒ、及び０．１７％のＡｇを示す。
【００５３】
２２gのこの触媒を、１００mlの直径３mmのガラス球とブレンドし、対照実施例１において使用したものと同じ反応器中に装填した。以下の手順によって触媒を活性化した；（１）反応器を、１００cc／分のＮ₂ガス流中で２３０°Fに加熱し、（２）２００cc／分のＨ₂をＮ₂ガス流に加え、３時間２３０°Fで保持し、（３）Ｎ₂ガスを止め、Ｈ₂ガス流を３００cc／分に増大させ、（４）反応器温度５７２°Fにまで加熱し、３時間５７２°Fで保持し、次に反応器を３０cc／分のＨ₂ガス流中で１４７°Fに冷却した。
【００５４】
実施例１０Ａにおいて使用したものと同じ供給物中のアセチレン型不純物を、選択的水素化によって除去した。選択的水素化を、１４２°Fの一定温度で実行した。しかしながら、最初の７３時間の運転時間の間、炭化水素及び水素供給速度は、反応器圧力１１９psigでそれぞれ３．７ml／分（６．１ＷＨＳＶ）及び４５scc／分であり、次に、１０８psigでそれぞれ６．１ml／分（１０．１ＷＨＳＶ）及び７４．２scc／分に変更された。１４５時間の運転時間の後に、触媒を、１００℃及び１０８psigで、７４．２scc／分のＨ₂流中で５時間、ベンゼン（１０ml／分）を用いて洗浄した。選択的水素化を、ベンゼン洗浄の直前と同じ条件で２４時間続けたが、ベンゼン（０．６ml／分）を混合Ｃ₄供給物と同時に反応器に供給した。この後、次の１８時間、供給速度を、１０ml／分の混合Ｃ₄供給物、１ml／分のベンゼン、及び９０scc／分のＨ₂に変更した。次いで、次の３０時間、供給速度を、反応器圧力９５psigで１５ml／分の混合Ｃ₄供給物、１．５ml／分のベンゼン、及び１１２scc／分のＨ₂に増大させた。この後、選択的水素化を、水素速度を９５scc／分に低下させて２４時間実行し、その間、他のプロセスパラメータを同じ条件で保った。次いで、次の６６時間、供給速度を、１０ml／分の混合Ｃ₄供給物、１ml／分のベンゼン、及び５４scc／分のＨ₂に低下させ、その間、他のプロセスパラメータを同じ条件で保った。
【００５５】
実施例１０Ａ及び１０Ｂの結果を、対照実施例２と共に図１０及び１１に示す。図８に示すように、パラジウムを用いて促進しなかった銅触媒は、高濃度のアセチレン型不純物を取り扱う際に非常に低い活性を有した。しかし、本発明において開示する手法において銅触媒をパラジウムを用いて促進した場合、触媒活性は劇的に改良された。驚くべきことに、本パラジウム促進銅触媒は、市販のＰｄ選択的水素化触媒よりもはるかに優れた活性を有する。さらに驚くべきことに、本パラジウム促進触媒はまた、そのはるかに高い活性にもかかわらず、アセチレン類の同じ転化において、市販のパラジウム触媒に勝る優れた１，３−ブタジエン収率を有する。また、本パラジウム促進触媒の失活速度は、市販のＰｄ触媒または非促進銅触媒よりもはるかに良好だった。この実施例は、高アセチレン型供給物の選択的水素化のための本パラジウム促進銅触媒の、パラジウム触媒または非促進銅触媒に勝る優れた性能を明確に証明する。
【００５６】
実施例１１
ガンマアルミナ（ＵＣＩから得たもので、１／８インチの押出物であり、表面積約２６０m²/g）を粉砕して１０〜２０メッシュの顆粒にした。このアルミナの供給者によれば、このアルミナの原料は、対照実施例１において使用したアルミナと同一だった。しかし、この顆粒状アルミナは、対照実施例１において使用したアルミナ（０．７９２g/ccのＡＢＤ）よりも低いＡＢＤ（０．５０g/cc）を有する。１２８mlの脱イオン水中の３０gのＣｕ（ＮＯ₃）₂．６Ｈ₂Ｏ、０．９３gのＮｉ（ＮＯ₃）₂．６Ｈ₂Ｏ、０．０４７gのＡｇＮＯ₃、０．３９６Ｃｒ（ＮＯ）₃．９Ｈ₂Ｏ及び０．３９６Ｃｏ（ＮＯ₃）₂．６Ｈ₂Ｏの溶液を作製した。ロータリーエバポレーターを使用して、７０gの顆粒状アルミナに上記の溶液を含浸させた。含浸生成物を、１１０℃、真空オーブン中で一晩乾燥した後に、４００℃、マッフル炉中で３時間か焼した。１８gのこの触媒を、１１０mlの直径３mmのガラス球とブレンドし、対照実施例１におけるものと同じ反応器中に装填した。以下の手順によって触媒を活性化した；（１）反応器を、１００cc／分のＮ₂ガス流中で２３０°Fに加熱し、（２）２００cc／分のＨ₂をＮ₂ガス流に加え、次に３時間２３０°Fで保持し、（３）Ｎ₂ガスを止め、Ｈ₂ガス流を３００cc／分に増大させ、（４）反応器温度６６２°Fにまで加熱し、３時間６６２°Fで保持し、次に反応器を３０cc／分のＨ₂ガス流中で１４７°Fに冷却した。
【００５７】
対照実施例１において使用したものと同じ供給物を選択的に水素化して、アセチレン型不純物を圧力１１９psigで除去した。最初の２９時間の運転時間の間、供給炭化水素及び水素速度は、それぞれ１．８cc／分（３．６ＷＨＳＶ）及び２５．７sc.／分だった。次いで、次の２４時間の運転時間の間、供給速度を、炭化水素の場合に２．４cc／分（４．９ＷＨＳＶ）、水素速度の場合に３４．３sc.／分に増大させた。この後、ランの終了まで、供給速度を炭化水素の場合に３cc／分（６．１ＷＨＳＶ）にさらに増大させたが、水素供給速度を３０sc.／分に低下させた。
【００５８】
この実験の試験結果と対照実施例１及び４の試験結果との比較を、担体アルミナのＡＢＤが触媒性能に及ぼす効果を証明するために、図１２及び１３に示す。この実施例におけるより低いＡＢＤのアルミナ（より高い多孔性を意味する）を使用して製造した触媒は、対照実施例１及び４において使用したより高いＡＢＤのアルミナよりも優れていた。この実施例及び対照実施例１におけるアルミナは同じ原料から製造された。しかし、この実施例において使用するより低いＡＢＤのアルミナは、アセチレン型不純物を除去する際により有効な触媒をもたらす。この実施例における触媒は、対照実施例１におけるものよりも良好な１，３−ブタジエン収率を有する。対照実施例４における触媒を製造するために使用したアルミナは、本発明において開示する表面積の好ましい範囲に入る表面積を有する。しかし、対照実施例４におけるアルミナのＡＢＤは０．９８g/ccであり、本発明において開示する好ましいＡＢＤ（＜０．６５g/cm³）よりも高い。対照実施例４における触媒がアセチレン型不純物を除去する際の有効性は、ほぼ対照実施例１と実施例１１との間に入る。実施例１１と対照実施例４とで、１，３−ブタジエンの収率の差はほとんどない。
【００５９】
実施例１２
比較的に高濃度のアセチレン型不純物を含む供給物の選択的水素化のためのパラジウム促進銅触媒の優れた性能を証明するために、この実施例を実行した。
【００６０】
パラジウムを用いて促進された銅触媒を、本発明に従って製造した。実施例５において使用したアルミナを、９００℃で３時間、空気中でか焼した。１０重量％の硝酸中の４．６１gの１０重量％のＰｄ（ＮＯ₃）₂溶液（オールドリッチ ３８，００４−０：１０重量％のＰｄ（ＮＯ₃）₂）を、６．３７８gの脱イオン水を用いて希釈することで作製した硝酸パラジウム溶液中に、１．８６６gのＣｕ（ＮＯ₃）₂２．５Ｈ₂Ｏを溶解させることで、混合溶液を作製した。５．５６gのこの混合溶液を、アトマイザーを使用して３０gのか焼したアルミナ球表面に噴霧し、その間、アルミナ球は平坦な表面上をあちらこちらに転がり回り、次に、噴霧済みの生成物を１１５℃、真空オーブン中で乾燥した。乾燥した生成物を、２５０℃で２時間、空気中でか焼した。
【００６１】
１８gのこの触媒を、１１０mlの直径３mmのガラス球と混合し、対照実施例１において使用したものと同じ反応器中に装填した。実施例１１において説明したものと同じ方法で、触媒を活性化した。対照実施例３において使用したものと同じ供給物中のアセチレン型化合物を、選択的水素化を実行することで除去した。選択的水素化を、１４２°Fの一定温度及び１０８psigで実行した。炭化水素供給速度を、ランの終了まで１０ml／分（２０．２ＷＨＳＶ）で保った。しかしながら、４４scc／分〜９０scc／分の範囲内の水素流量の変動がランの最中に生じた。
【００６２】
この実施例１２及び対照実施例３の結果を、図１４及び１５に示す。本パラジウム促進銅触媒の、従来のパラジウム触媒に勝る優れた触媒活性が明確に証明される。実施例１２における供給速度は対照実施例３のものよりも少なくとも４倍高いにもかかわらず、本パラジウム促進銅触媒は、対照実施例３における従来のパラジウム触媒に勝る１，３−ブタジエンの優れた収率（図１４において回収率として表す）を有しながら、２０ppm未満のＣ₄アセチレン類を含む生成物を生じることができる。Ｃ₄アセチレン類の回収率を、１００％対Ｃ₄アセチレン類の％転化によって定義する。例えばＣ₄アセチレン類の０％回収率は、Ｃ₄アセチレン類の１００％除去に等しく、１００％の１，３−ブタジエン回収率は、１，３−ブタジエンの０％転化に等しい。
【００６３】
生成物中のエチルアセチレン対ビニルアセチレンの比を、図１５に示す。本パラジウム促進銅触媒は、ビニルアセチレンに対する反応性が従来のパラジウム触媒よりもはるかに高い。本パラジウム促進銅触媒は、非促進銅触媒よりも約１桁高い活性を有する。本パラジウム促進銅触媒が、従来のＰｄ触媒よりも数倍高い活性を有し、しかもなおこれが１，３−ブタジエンを保持する優れた選択性を有することは予想外である。
【図面の簡単な説明】
【００６４】
【図１】アセチレン類の選択的水素化のために上部に本銅触媒を有するＣＤ反応器の略図である。
【図２】アセチレン類の選択的水素化のために上部に本銅触媒を有し、メルカプタン類及びジオレフィン類を反応させるために下部にＶＩＩＩ族触媒を有するＣＤ反応器の略図である。
【図３】実施例５のアルミナ担体及び触媒の細孔分布のグラフ図である。
【図４】実施例の対照１、実施例５及び実施例６の生成物中の全生成物アルキン類のグラフ図である。
【図５】実施例の対照１、実施例５及び実施例６の全１，３−ブタジエン生成物の収率のグラフ図である。
【図６】ＣＤにおける実施例７の結果のグラフ図である。
【図７】実施例５（非ＣＤ）及び実施例８（ＣＤ）の生成物中の全アルキン類のグラフ図である。
【図８】実施例５（非ＣＤ）の１，３−ブタジエン生成物及び実施例８（ＣＤ）を比較するグラフ図である。
【図９】使用された触媒の溶媒処理の利益のグラフ図である。
【図１０】Ｐｄ促進Ｃｕの利益を示すために実施例１０Ａ及び１０Ｂを比較するグラフ図である。
【図１１】１，３−ブタジエン製造に及ぼすＰｄ促進Ｃｕの利益を示すために実施例１０Ａ及び１０Ｂを比較するグラフ図である。
【図１２】アセチレン類の除去の場合の本発明によるＡＢＤの利益のグラフ図であり、対照実施例１及び４並びに実施例１１を比較したものである。
【図１３】１，３−ブタジエン生成物の場合の本発明によるＡＢＤの利益のグラフ図であり、対照実施例１及び４並びに実施例１１を比較したものである。
【図１４】本パラジウム促進銅触媒の利益のグラフ図であり、実施例１２と対照実施例３とを比較したものである。
【図１５】実施例１２と対照実施例３とを比較することによる、本パラジウム促進銅触媒を従来のパラジウム触媒と区別する化学的指紋のグラフ図である。【Technical field】
[0001]
The present invention relates to the selective removal of more unsaturated compounds from a mixture of unsaturated compounds. More specifically, the invention relates to the selective hydrogenation of acetylenic compounds from mixtures with dienes such as 1,3-butadiene. The present invention provides both a novel catalyst and a method for the selective hydrogenation of acetylenes that are miscible with other unsaturated compounds.
[Background Art]
[0002]
Supported copper and palladium catalysts have been the preferred catalysts for removing acetylene-type impurities in olefin streams by selective hydrogenation. Copper catalysts selectively hydrogenate acetylene-type compounds without substantial hydrogenation of olefins and diolefins (referred to herein as selectivity for retaining olefins), but mainly It has relatively low activity and short cycle times due to polymer deposition on the catalyst surface. Palladium catalysts have excellent activity and much longer cycle times than copper-based catalysts, but have lower selectivity for acetylenes. Small amounts of silver or gold have been added to palladium catalysts as modifiers to improve the olefin selectivity of the palladium catalyst.
[0003]
Fr 1 253 947 (1960) disclosed copper catalysts for the selective hydrogenation of acetylenic compounds in diolefin or monoolefin streams. Selective hydrogenation was performed in the vapor phase. Copper having a purity of 99.9-99.999% is converted to a high surface area (25-300 m ^Two / g) supported on the carrier surface. The copper content of the catalyst was in the range of 5-20%. The catalyst may comprise less than 0.1% of another metal (based on the metal content of the catalyst), for example Fe, Ni, Ru, Rh, Pd, Ir or Pt as cocatalyst. Selective hydrogenation was performed both in the vapor phase and in the liquid phase. U.S. Pat. Nos. 4,440,956 (1984) and 4,493,906 (1985) describe improved copper catalysts supported on very specific alumina surfaces, such as gamma alumina made from aluminum alkoxides, comprising liquid hydrocarbons. A copper catalyst useful for removing alkynes in a stream has been disclosed. The patentee states that gamma alumina should have 60-90% of the pores have a pore diameter of about 40 Å-120 Å and less than 25% and more than 2% have a pore diameter of 1000 Å-10,000 Å. Characterized as having Angstrom. The nitrogen surface area of alumina is about 68-350m ^Two / g. The catalyst contained 3 to 13% by weight of Cu. The catalyst comprised a minor amount of at least one multivalent activator metal selected from the group consisting of silver, manganese, cobalt, nickel and chromium. High purity alumina (especially sodium (should be less than 0.15% by weight) and Fe _Two O _Three (In terms of content (less than 0.06% by weight)) was claimed to be a requirement due to surface area shrinkage caused by frequent catalyst regeneration.
[0004]
Ger 2 109 070 (1970) disclosed a copper (26%)-zinc oxide catalyst for the selective hydrogenation of acetylenic compounds in a 1,3-butadiene stream in the vapor phase.
U.S. Pat. No. 4,174,355 (1979) disclosed a process for removing .alpha.-acetylene from a diolefin stream by non-selective hydrogenation. In the absence of hydrogen and oxygen, feed vapor and CuO and / or Ag supported on α-alumina surface _Two The alkynes were removed by contact with O.
[0005]
U.S. Pat. No. 4,533,779 (1985) discloses alumina (1-100 m) for the selective hydrogenation of acetylenic compounds. ^Two / g), a palladium / gold catalyst supported on a support surface. The contents of palladium and gold in the catalyst were in the range of 0.03-1% by weight and 0.003-0.3% by weight, respectively.
[0006]
U.S. Pat. No. 4,831,200 (1989) disclosed a process for the selective hydrogenation of alkynes in an olefin stream, such as a mixture with 1,3-butadiene. Selective hydrogenation was performed sequentially in two stages. In the first step, the hydrocarbon feed was passed, together with hydrogen, at least partially in the liquid phase over a palladium catalyst such as that disclosed in US Pat. No. 4,533,779, discussed above. In the second stage, the product stream resulting from the first stage, again with hydrogen, at least partially in the liquid phase, such as those disclosed in the above-discussed U.S. Pat. Nos. 4,493,906 and 4,440,956 Passed over a fresh copper catalyst, resulting in a significantly reduced alkyne concentration in the finished product stream.
[0007]
U.S. Pat. No. 5,877,363 (1999) discloses mixed olefin rich C by using supported hydrogenation catalysts such as Pt and Pd. _Four A method for the selective hydrogenation of acetylenic impurities and 1,2-butadiene in a stream has been disclosed.
[0008]
In general, palladium catalysts are much more active than copper catalysts due to the selective hydrogenation of acetylenic compounds in olefin vapors. However, when attempting to remove high concentrations (> 2000 ppm) of total alkynes in the stream to less than about 500 ppm of total alkynes, especially when acetylenes are reduced to less than 200 ppm, the palladium catalyst can be used to convert 1,3-butadiene to 1,3-butadiene. It shows low selectivity for retaining such diolefins. In industrial practice, the non-selectivity of the palladium catalyst is undesirable because it results in the loss of 1,3-butadiene.
[0009]
On the other hand, copper catalysts are highly selective at retaining diolefins such as 1,3-butadiene by being very selective for hydrogenation of acetylenes. However, the activity of the copper catalyst is low. Also, due to the rapid deactivation caused by the deposition of the polymeric material on the catalyst surface, the cycle time of the catalyst is undesirably short for feed streams containing more than about 2000 ppm total alkynes. Even though the hydrogenation is performed in the liquid phase, some of the polymer deposited on the copper catalyst surface has little solubility in the liquid product stream under selective hydrogenation conditions. For these two reasons, copper catalysts require improvements to the selective hydrogenation of mixed olefin feeds containing relatively high levels of total alkynes.
DISCLOSURE OF THE INVENTION
[0010]
The present invention comprises a catalyst comprising a copper component comprising about 0.1 to 25% by weight, preferably 0.2 to 20% by weight of Cu; % Of the silver or gold modifier is in the range of 0 to 15% by weight, preferably 0 to 10% by weight; the zinc oxide modifier is in the range of 0 to 25% by weight, preferably 0 to about It is in the range of 15% by weight. The silver modifier moderates catalytic activity and improves olefin yield and cycle time. Zinc oxide modifiers improve the yield of olefins such as 1,3-butadiene and slightly improve the catalytic activity. Zinc oxide-modified copper catalysts are particularly very effective for removing vinylacetylene impurities while having a very high yield of 1,3-butadiene. In a preferred embodiment, the catalyst component is deposited on the support surface.
[0011]
Preferred carriers have an average pore diameter greater than about 200 Angstroms, no micropores, a total pore volume greater than about 0.65 cc / g, and preferably about 230 m ^Two have a BET surface area of less than / g. The copper catalyst is promoted, preferably with a Group VIII metal such as palladium, to improve the low activity of the copper catalyst. The product stream typically contains less than 20 ppm of total alkynes. The copper catalyst and the palladium promoted copper catalyst may also be adjusted with zinc oxide to improve the performance of the catalyst. Two or more copper catalysts promoted with different levels of palladium were charged to the reactor. Also preferably, the copper catalyst is adjusted with silver, gold or both silver and gold to reduce polymer formation by the copper component of the catalyst and improve the yield of olefins such as 1,3-butadiene. Prevents the loss of copper and palladium by leaching into the liquid phase of hydrocarbons.
[0012]
A method of removing acetylene-type compounds by contacting a hydrocarbon stream containing a small amount of the acetylene-type compounds with the catalyst of the present invention in various arrangements and shapes is also a part of the present invention.
BEST MODE FOR CARRYING OUT THE INVENTION
[0013]
The selective hydrogenation is preferably carried out at least partially in the liquid phase, for example by using one or more catalytic distillation (CD) units. Thus, a novel process is provided to allow selective hydrogenation to be carried out in one step at higher throughput rates, while still maintaining high selectivity and long catalyst life while retaining olefins such as dienes. It is highly desirable to provide an improved copper catalyst. In the present invention, this object is achieved by carrying out the selective hydrogenation in a single reactor having a highly active and still highly selective copper catalyst. Preferably, the selective hydrogenation is performed at least partially in the liquid phase by using a catalytic distillation (CD) unit. The distillation column is charged with two or more copper catalysts promoted using different levels of Group VIII elements such as palladium, ruthenium, nickel, and the like, and conditioned with zinc oxide and Group IB elements. A preferred cocatalyst is palladium. Promoting the copper catalyst with palladium is highly desirable when handling high acetylenic feeds. The data show that copper becomes much more active when alloyed with palladium, and that there is a slight loss of selectivity for retaining olefins such as 1,3-butadiene or 1-butene. Show. By alloying copper with palladium, the chemistry of the present copper-palladium catalyst changes from conventional palladium or palladium-silver catalysts. The nature of the change is demonstrated in Example 12. The ratio of ethyl acetylene to vinyl acetylene in the product stream obtained from the present invention is much higher than the product obtained from conventional palladium catalysts, because the present copper-palladium catalyst contains vinyl acetylene and ethyl acetylene. Is significantly different from conventional palladium or palladium-silver catalysts. Therefore, C _Four The difference in ratio for a given conversion of acetylenes is a fingerprint that distinguishes the chemical catalytic properties of the present copper-palladium catalyst from conventional palladium catalysts.
[0014]
Mixed C to produce a clean 1,3-butadiene concentrated product _Four In handling the feed stream, a copper catalyst may be charged into the debutanizer distillation column to provide a CD reactor. The feed to the catalytic distillation column is fed to the central section of the column, preferably below the catalyst bed. The product is recovered as overhead distillate. The heavier product is recovered as the bottom product. The palladium content of the copper catalyst charged into the CD reactor gradually decreases as it rises from the bottom section to the top section of the catalyst bed. The catalyst is charged above the point of feed to the distillation column. Hydrogen is fed to a location in the bottom section of the distillation column, either together with the hydrocarbon feed or separately. The optimum ratio of hydrogen to total alkynes in the catalytic reaction zone depends not only on the Cu content of the catalyst but also on the Cu / Pd weight ratio. Thus, depending on the composition of the catalyst in the reactor, hydrogen is preferably fed to more than one location along the catalytic distillation column or fixed bed. The palladium component of the catalyst also improves the cycle time of the catalyst. It is not known how this additional benefit of the copper catalyst promoted with Pd occurs, but the unsaturated precursors leading to the polymeric material are more effectively hydrogenated and The deposition of the polymer material may be slower or negligible. Polymeric materials can have higher solubility in product vapors than polymers formed on unpromoted copper catalyst surfaces. Thus, the precursor and polymer materials are effectively flushed from the catalyst to the bottom of the catalytic distillation column, resulting in a cleaner catalyst surface that is continuously regenerated. Preferably, the copper component of the catalyst is adjusted with a Group IB element, such as silver and / or gold, or both to further reduce polymer formation and improve diene selectivity, and to remove copper and palladium metal from the catalyst. Improve the leaching point gradually.
[0015]
The catalyst was further conditioned with zinc oxide to improve catalytic activity, yield of olefins such as 1,3-butadiene, cycle time of the catalyst, and copper and palladium by leaching slowly from the catalyst. Losses may be reduced. In the case of a Cu—Zn—Al methanol synthesis catalyst produced by coprecipitation of a mixed solution of nitrates, Cu (II) ions are converted to a zinc oxide phase of a copper-zinc oxide-alumina catalyst (produced by a coprecipitation method). And its concentration can be as high as about 25 atomic% (TM Yurieva, et al. React. Kinet. Catal. Lett., 29, pp. 55-61, 1985). All copper catalysts disclosed in this invention have been observed to have a high content of active hydrogen species capable of hydrogenating olefins in the absence of hydrogen, whether or not the catalyst contains zinc oxide. .
[0016]
Hydrogenation may be performed in two stages. For example, selective hydrogenation can be performed as shown in FIG. 2 using two CD reactors, or a combination of a CD reactor and a fixed bed reactor, or two fixed bed reactors. In operation of the fixed bed reactor, the reactor effluent stream from the first reactor is cooled before entering the second reactor to remove heat from the hydrogenation reaction exotherm, More than one reactor may be required. It may also be possible to recycle the reactor effluent in a fixed bed reactor operation to dilute the heat of the hydrogenation reaction. If desired, the polymer may be flushed from the catalyst in a reactive distillation manner or in a straight-pass manner using a material in which the polymer deposited on the catalyst surface is soluble. Examples of such solvents include tetrahydrofuran, furan, 1,4-dioxane, ethers, gamma-butyrolactone, benzene, toluene or mixtures thereof. After separating the product from the solvent, as shown in FIG. 1, the solvent is recycled and returned to the reactor. Another approach to extending catalyst life is to wash the catalyst intermittently with a liquid solvent at a temperature in the range of about 40 ° C. to 350 ° C. to remove deposited polymer from the catalyst. While flushing the polymer from the catalyst, a small amount of hydrogen gas, if desired, is passed through the catalyst bed along with the solvent. C _Four In performing the selective hydrogenation of actelyenes in a stream in a CD mode, if the boiling point of the solvent is above about 100 ° F., the solvent may be added to the top of the catalytic zone of the catalytic distillation reactor. The solvent then flows downflow at the bottom of the column. In a straight pass reactor, a solvent may be fed to the reactor along with the reactant feed stream. During both embodiments, it is desirable to apply sufficient pressure so that at least 0.2 mol% of the acetylenes in the feed stream is in the liquid phase containing solvent and hydrocarbons in the reaction zone. .
[0017]
The preferred support used for the preparation of the catalyst in the present invention is a mesoporous material and should have a relatively large pore volume. As the average pore diameter of the supporting material increases, the pore volume increases as well, but both the surface area of the material and the ABD (apparent bulk density, often referred to as packed density) Decreases. Preferably, the carrier will have no micropores, preferably no pores less than about 30 angstroms in diameter. In general, the pore size distribution and size of the pores play an important role in catalytic performance, as the deposition of heavy materials on the catalyst surface causes catalyst deactivation and excessive reaction to reduce the selectivity of the desired material. One of the preferred supports in the present invention is a transition alumina. The desired alumina pores are mainly composed of pores having a diameter greater than 100 angstroms. About 85%, preferably about 90%, of the pores will have a pore diameter greater than 100 angstroms as measured by nitrogen porosimetry. Preferred aluminas have an average pore diameter of greater than about 100 angstroms, preferably greater than 120 angstroms, greater than about 0.65 cc / g (as measured by nitrogen porosimetry), and preferably greater than 0.70 cc / g. Also large total pore volume, preferably about 230 m ^Two / g, most preferably 30-200 m ^Two / g BET surface area, about 0.70g / cm ^Three It will have an apparent bulk density (ABD) of less than. The pores of alumina are composed of pore diameters of various sizes. Within a certain range of alumina surface area, the pore distribution of the alumina can be manipulated depending on how the alumina was produced and calcined. Unlike the alumina disclosed in U.S. Pat. No. 4,440,956, preferred aluminas in the present invention have pores in which at least 30%, preferably at least 50%, of the pores have a diameter greater than 100 Angstroms, and It will have a total pore volume of greater than 0.65 cc / g, preferably about 0.75 cc / g.
[0018]
The preferred aluminas disclosed in the present invention can be made by a number of techniques well known to those skilled in the art of making so-called activated alumina. One of the preferred aluminas disclosed in the present invention can be made by the so-called oil dropping gelatiion technique. Examples of the prior art are disclosed in U.S. Patent Nos. 2,620,314 (1952) and 4,273,735 (1981). Spherical alumina is prepared from an aluminum hydroxychloride sol prepared by digesting aluminum metal in an aqueous hydrochloric acid solution. The spherical alumina sol material in the form of droplets is gelled in a basic liquid oil phase, followed by aging, washing, drying and calcining (at various temperatures depending on the desired properties of the alumina), Transition alumina. Alternatively, preferred spherical aluminas can be produced using dispersed boehmite or pseudo-boehmite alumina sols by an oil-drop gelation technique. An example of the prior art is disclosed in U.S. Pat. No. 4,179,408 (1979). Alumina sols are made by dispersing suitable boehmite, pseudo-boehmite, or a mixture of boehmite and pseudo-boehmite alumina in acidic water. The pseudo-boehmite or boehmite raw material is obtained by hydrolyzing and crystallizing an aluminum alkoxide or by reacting sodium aluminate with an aluminum salt such as aluminum sulfate to crystallize. Various boehmite aluminas or dispersed boehmite alumina sols are commercially available. Condea is one of the suppliers. In order to produce a preferred spherical alumina having a pore structure disclosed in the present invention, Disperal HP 14/2, Dispal 11N7-80, Dispal 23N4-20, Disperal. HP14, Deperal 40, Pural 200, Pral 100, Pral NG, etc., or mixtures thereof can be used. Other boehmite aluminas such as Catapal C1, Pral SB, Disperal P2, etc. are not preferred raw materials for the production of the preferred alumina disclosed in the present invention. Such materials provide similar aluminas as disclosed in U.S. Patents 4,493,906 and 4,440,956.
[0019]
The preferred alumina in extrudate form can also be prepared by extruding the preferred boehmite alumina discussed above and calcining at an elevated temperature of about 550C to 1200C. Generally, transition aluminas are various mixtures of crystalline aluminas, such as amorphous, γ, χ, δ, η, ρ, θ, α, etc., whose surface area is more stable by repeated exposure to high temperature atmospheres. Tend to shrink due to slow crystallization leading to a different crystal form. In particular, this surface area shrinkage is accelerated in the presence of atmospheric moisture or trace amounts of sodium in alumina or both. If the gamma alumina is in the desired form, calcination is usually performed at a temperature of about 550C to 700C. Unlike the aluminas disclosed in U.S. Pat. Nos. 4,493,906 and 4,440,956, alumina supports were prepared in an oil-drop gelation procedure using an aluminum hydroxychloride sol containing very little chlorine. The small amounts of sodium or chlorine in alumina disclosed in the present invention do not usually cause significant problems when operating catalytic distillation with solvents or fixed bed operation due to long catalyst cycle times. .
[0020]
The preferred physical forms of alumina in the present invention are spheres, extrudates, pellets and granules, which have a diameter of less than about 1/4 inch, preferably 1/8 inch, and in the case of extrudates or pellets, lengths. It has a length of less than about 1/2 inch, preferably less than 1/4 inch in length.
[0021]
The copper component of the catalyst is placed on a preferred alumina surface by various impregnation techniques using aqueous solutions of cupric salts such as cupric nitrate, cupric acetate, and the like. The impregnation product is calcined at about 100-500 ° C, preferably 200-400 ° C, to decompose the salts and obtain a copper oxide-alumina product. The silver and zinc oxide modifiers are incorporated into the catalyst by co-impregnation of a silver salt such as silver nitrate and a copper salt with a zinc salt such as zinc nitrate. If desired, they are incorporated into the copper catalyst by double impregnation. The zinc oxide modifier or both the silver and zinc oxide modifiers are placed on the alumina support surface prior to impregnation with the solution of the copper compound. The impregnation product is calcined at about 100-650 ° C, preferably 100-600 ° C, to obtain a copper oxide-silver oxide-alumina catalyst or a copper oxide-silver oxide-zinc oxide-alumina catalyst. Yet another approach can be used to produce a zinc oxide-modified copper catalyst, which comprises dropping an alumina sol containing a desired amount of a zinc salt or both a zinc salt and a copper salt into a basic oil phase. By forming a gel followed by aging, washing and calcining in the temperature range of 450-1200C.
[0022]
The palladium promoter is catalyzed by simultaneous impregnation of a palladium compound solution such as palladium (II) nitrate, palladium (II) acetate, palladium (II) acetylacetonate and a copper salt solution or a solution containing a copper salt and a silver salt. Take it inside. Various impregnation techniques can be used, but a palladium compound solution, or a mixed solution of a palladium compound and a copper compound, or a palladium compound and a copper compound and a silver compound, or a palladium compound, a copper compound, a silver compound, and a zinc compound A preferred impregnation technique is spray coating impregnation using an atomizer. It is highly desirable to spray the solution uniformly on the surface of the carrier. It is also highly desirable to use a compressed gas atomizer to generate fine mist of palladium solution. When spraying various palladium solutions onto a support surface such as alumina, the desired volume of the solution is determined by the total pore volume of the impregnated support (the weight of the support, the pore volume per unit weight of the support). Less than about 90% by volume, preferably less than about 85% by volume.
[0023]
When producing highly active copper catalysts promoted with palladium, impregnation of the catalyst components can be carried out in one or two stages. In a two-stage impregnation, the first stage impregnation technique typically employs an incipient pore impregnation technique to deposit a solution of a copper compound, or a copper and zinc compound, or a copper compound on an alumina support. , Zinc and silver compound, or a mixed solution containing zinc and silver compound, followed by drying at a temperature of about 100 to 250 ° C and calcining at a temperature of 250 to 700 ° C, preferably 300 to 550 ° C. In the second stage, the product resulting from the first stage is added to a solution of a palladium compound, preferably a palladium and copper compound, or a palladium and copper and silver compound, or a palladium, copper, zinc and silver compound Or a mixed solution of palladium, silver, and a zinc compound is impregnated by a spray coating technique using an atomizer, followed by drying at a temperature of 100 to 250 ° C, and about 250 to 650 ° C, preferably 300 to 550 ° C. Calcination at a temperature of ° C.
[0024]
Another preferred method of incorporating palladium into the copper catalyst is a copper oxide-alumina catalyst, copper oxide-alumina, oxidized solution of a solution of a palladium compound or a mixed solution of a palladium compound such as palladium nitrate and a silver compound such as silver nitrate. Spray coating impregnation on a copper-zinc oxide-alumina catalyst or a copper oxide-silver oxide-zinc oxide alumina catalyst surface, during which the copper catalyst spheres roll over a flat surface inclined at an appropriate angle. A relatively high loading (> 0.15% by weight) of palladium on the copper catalyst surface is desirable for treating a feed containing a relatively high content (> -4000 ppm) of all acetylenic compounds. The combination of co-impregnation and spray coating impregnation is the most desirable approach for high palladium loading on the catalyst surface. It is very important to produce fine mist of palladium solution for spray coating impregnation. If a copper catalyst promoted with greater than about 0.15% Pd is desired, a combination of co-impregnation and spray coating impregnation is generally preferred. The impregnation product is calcined at about 100-400 ° C, preferably 100-350 ° C, in air to produce a palladium promoted copper, copper-silver or copper-silver-zinc catalyst.
[0025]
If desired, a catalyst can be produced by impregnating a mixed solution of metal salts on the surface of the alumina powder having the preferable physical properties of the carrier described above. The raw materials for producing such alumina powders are suitable boehmite powders and pseudo-boehmite powders, for example Disperal HP 14/2. The raw material is calcined at a temperature of about 400C to about 750C before impregnation. The impregnation product is calcined in air at a temperature of about 250-550 ° C and shaped into extrudates or pellets of the desired size. If desired, the impregnation product is shaped into extrudates or pellets, and the shaped material is then calcined in air at elevated temperatures of about 250C to 550C.
[0026]
The catalyst activation is carried out at about 60-400 ° C., preferably 100-350 ° C., in a gas stream comprising hydrogen. The content of hydrogen in the gas gradually increases during the activation, from about 5% to more than 50% by volume in an inert gas such as nitrogen. During catalyst activation, a sufficient amount of gas flow is preferred as it is not expected that water vapor condensation on the catalyst surface will occur. The length of activation depends on the amount of catalyst in the reactor, the hydrogen content in the gas and the activation temperature. In the laboratory, for less than about 100 grams of catalyst, 30 minutes to about 10 hours is sufficient. In industrial practice, much longer activation times will generally be required. After activation of the catalyst, the hydrogen remaining in the reaction zone is flushed with an inert gas. At the beginning of the selective hydrogenation, the content of unsaturated compounds in the feed stream should be kept at very low levels in the catalytic reaction zone by using an inert diluent such as a saturated hydrocarbon, This is done until most of the hydrogen content in the activated catalyst has been consumed. Due to the relatively high content of copper on the catalyst surface, the activated catalyst contains a relatively large amount of active hydrogen which can cause run away temperatures in the catalyst bed.
[0027]
In handling actual feed streams in industrial practice, it is necessary to protect selective hydrogenation catalysts, such as copper catalysts, from poisoning by sulfur compounds, such as alkyl mercaptans. Catalysts such as Pd, Ni, etc. to protect the selective hydrogenation catalyst from poisoning by alkyl mercaptans in the feed stream or selective hydrogenation catalysts disclosed in the present invention to maximize the mercaptan reaction The sulfur impurities are converted to heavier sulfur compounds by reacting with olefins, acetylene type compounds or dienes on an otherwise optimized optional catalyst. Heavier sulfur products are removed from lighter components by simple distillation. During this mercaptan removal operation, sulfur compounds are converted to H _Two It is very important not to generate S, because H _Two S will poison the selective copper hydride catalyst. In the CD unit, this removal of the mercaptans can be performed simultaneously with the selective hydrogenation in a single distillation column. A catalyst for forming higher boiling organic sulfides from mercaptans, such as those disclosed in U.S. Patent Nos. At the bottom of the selective hydrogenation catalyst bed. Heavier sulfur compounds are removed as bottom products from the CD column before entering the selective hydrogenation reaction zone, thereby protecting the selective hydrogenation catalyst from sulfur impurities. It is important to maintain a minimum amount of hydrogen in this mercaptan reaction zone so that no hydrogen sulfide is produced. If excess hydrogen is available, some of the mercaptans may be converted to hydrogen sulfide by hydrodesulfurization of the alkyl mercaptans or sulfides. To prevent the formation of hydrogen sulfide, it may be necessary to adjust the hydrogen content in the mercaptan reaction zone differently from that in the catalytic selective hydrogenation reaction zone.
[0028]
Comparative Example 1
A copper catalyst was prepared according to Example 1 of U.S. Patent No. 4,440,956. Gamma alumina (CS 331-1 from UCI, 1/16 inch extrudate, surface area 265 m ^Two / g) was calcined at 700 ° C. for 3 hours in an ambient atmosphere before use. The ABD changed little before and after calcination. The calcined alumina had an ABD of 0.792 g / cc. 28.7 g Cu (NO in 110 ml deionized water) _Three ) _Two . 2.5H _Two O, Ni (NO _Three ) _Two . 6H _Two O, 0.04 g of AgNO _Three , 0.34 g of Cr (NO _Three ) _Three . 9H _Two O and 0.34 g of Co (NO _Three ) _Two . 6H _Two A solution of O was made. Using a rotary evaporator, 60 g of UCI alumina was impregnated with the above solution. The impregnated product was dried in a vacuum oven at 110 ° C. overnight and then calcined in a muffle furnace at 400 ° C. for 3 hours. The ABD of the catalyst was 0.87 g / cc. 22 g of this catalyst were blended with 100 ml of 3 mm diameter glass spheres and loaded into a vertical stainless steel reactor (1 inch diameter × 20 inch length) used as a conventional reactor. The catalyst was activated by the following procedure; (1) The reactor was charged with 100 cc / min N 2 _Two Heat to 230 ° F in a gas stream and (2) 200cc / min H _Two To N _Two In addition to the gas flow, then hold at 230 ° F. for 3 hours; _Two Stop gas, H _Two The gas flow was increased to 300 cc / min and (4) heated to a reactor temperature of 662 ° F. and held at 662 ° F. for 3 hours, then the reactor was cooled to 30 cc / min H2. _Two Cooled to 147 ° F in a gas stream.
[0029]
28 ppm by weight of methyl acetylene, 1034 ppm by weight of vinyl acetylene and 549 ppm by weight of ethyl acetylene, 45.23% by weight of 1,3-butadiene, 0.10% by weight of 1,2-butadiene, 6.05% by weight T-2-butene, 4.22 wt% c-2-butene, 15.36 wt% 1-butene, 18.05 wt% isobutene, 9.34 wt% n-butane, 1.30 % By weight of isobutane, as well as 0.19% by weight of another C _Four The stream was selectively hydrogenated to remove acetylenic impurities at a pressure of 119 psig. During the first 26 hours of operation, the feed hydrocarbon and hydrogen rates were 2.2 cc / min (3.6 WHSV) and 31.4 scc / min, respectively. The feed rate was then changed to 3 cc / min (5.0 WHSV) for hydrocarbons and 27 scc / min for hydrogen rates during the next 24 hours of operation. Thereafter, until the end of the run, the feed rate was 2.2 cc / min (3.6 WHSV) for hydrocarbons and 31.4 scc / min for hydrogen rates.
[0030]
Comparative Example 2
18 grams of palladium catalyst (2464F from UCI, 0.7% Pd / 1.4% Ag on alumina surface) was mixed with 110 ml of 3 mm diameter glass spheres and used in Control Example 1. Into the same reactor. 1 ml / min (measured at ambient temperature) isobutane and 10 cc / min 10% by volume H in He _Two The catalyst was activated at 180 ° F. by passing gas at 200 psig for 1 hour. 39 ppm by weight of methyl acetylene, 5974 ppm by weight of vinyl acetylene and 1119 ppm by weight of ethyl acetylene, 46.05% by weight of 1,3-butadiene, 0.15% by weight of 1,2-butadiene, 5.68% by weight T-2-butene, 3.95 wt% c-2-butene, 14.38 wt% 1-butene, 17.98 wt% isobutene, 9.24 wt% n-butane, 1.32 % By weight isobutane, as well as 0.54% by weight of the other C _Four The stream was selectively hydrogenated to remove acetylenic impurities therein. Selective hydrogenation was performed at a constant temperature of 147 ° F. However, during the first 79 hours of operation, the hydrocarbon and hydrogen feed rates were 3 ml / min (6.1 WHSV) and 36.8 scc / min, respectively, at a reactor pressure of 119 psig, followed by a reactor pressure of 108 psig. Was changed to 4.9 ml / min (9.9 WHSV) and 60 scc / min, respectively.
[0031]
Control Example 3
18 grams of palladium catalyst (CDT-3 from UCI, 0.2% Pd / 0.1% Ag on the surface of alumina) were mixed with 110 ml of 3 mm diameter glass spheres and used in Control Example 1. Was loaded into the same reactor as used in. 1 ml / min (measured at ambient temperature) isobutane and 10 cc / min 10% by volume H in He _Two The catalyst was activated at 180 ° F. by passing gas at 200 psig for 1 hour.
[0032]
39 ppm by weight of methyl acetylene, 5974 ppm by weight of vinyl acetylene and 1119 ppm by weight of ethyl acetylene, 46.05% by weight of 1,3-butadiene, 0.15% by weight of 1,2-butadiene, 5.68% by weight T-2-butene, 3.95 wt% c-2-butene, 14.38 wt% 1-butene, 17.98 wt% isobutene, 9.24 wt% n-butane, 1.32 % By weight isobutane, as well as 0.54% by weight of the other C _Four The stream was selectively hydrogenated.
[0033]
Control Example 4
Activated alumina (Alfa 31268), 3.2 mm pellet, surface area 90 m ^Two / g) into 10-20 mesh granules. Granular alumina had an ABD of about 1 g / cc. 28.7 g Cu (NO in 100 ml deionized water) _Three ) _Two . 2.5H _Two O, Ni (NO _Three ) _Two . 6H _Two O, and 0.04 g of AgNO _Three Was prepared. 60 g of granular alumina was impregnated with the above solution using a rotary evaporator. The impregnated product was dried in a vacuum oven at 110 ° C. overnight and then calcined in a muffle furnace at 400 ° C. for 3 hours. 18 g of this catalyst were blended with 110 ml of 3 mm diameter glass spheres and charged into the same reactor as in Control Example 1. The catalyst was activated by the following procedure; (1) The reactor was charged with 100 cc / min N 2 _Two Heat to 230 ° F in a gas stream and (2) 200cc / min H _Two To N _Two In addition to the gas flow, then hold at 230 ° F. for 3 hours; _Two Stop gas, H _Two The gas flow was increased to 300 cc / min and (4) heated to a reactor temperature of 662 ° F. and held at 662 ° F. for 3 hours, then the reactor was cooled to 30 cc / min H2. _Two Cooled to 147 ° F in a gas stream.
[0034]
The same feed used in Control Example 1 was selectively hydrogenated to remove acetylenic impurities at a pressure of 119 psig. During the first 26.5 hours of operation, the feed hydrocarbon and hydrogen rates were 1.8 cc / min (3.6 WHSV) and 25.7 scc / min, respectively. The feed rate was then changed to 2.4 cc / min (4.9 WHSV) for hydrocarbons and 22.1 scc / min for hydrogen rates during the next 24 hours of operation. Thereafter, the feed rate was again changed to 1.8 cc / min (3.6 WHSV) and 25.7 scc / min for hydrocarbons.
[0035]
Example 5
The copper catalyst was prepared according to the present invention using alumina (1/16 inch diameter spheres) produced by the oil drop gelation technique. Table 1 summarizes the physical properties of alumina. FIG. 1 shows the pore size distribution of alumina. Greater than about 90% of the pores were greater than 100 angstroms in diameter. 28.7 g Cu (NO in 110 ml deionized water) _Three ) _Two . 2.5H _Two O, Ni (NO _Three ) _Two . 6H _Two O, 0.04 g of AgNO _Three , 0.34 g of Cr (NO _Three ) _Three . 9H _Two O and 0.34 g of Co (NO _Three ) _Two . 6H _Two A solution of O was made. Using a rotary evaporator, 60 g of alumina was impregnated with the above solution. The impregnated product was further dried in a vacuum oven at 110 ° C. overnight before calcining in a muffle furnace at 400 ° C. for 3 hours. The physical properties of the catalyst are summarized in Table 2. As shown in FIG. 1, the pore structure of the copper catalyst was only slightly changed from the alumina carrier. 22 g of this catalyst were blended with 100 ml of 3 mm diameter glass spheres and charged into the same reactor used in Control Example 1. Catalyst activation was performed in the same manner as described in Control Example 1.
[0036]
The same feed used in Control Example 1 was selectively hydrogenated to remove acetylenic impurities at 119 psig. During the first 26 hours of operation, the feed hydrocarbon and hydrogen rates were 2.2 cc / min (3.6 WHSV) and 31.4 scc / min, respectively. The feed rate was then changed to 3 cc / min (5.0 WHSV) for hydrocarbons and 27 scc / min for hydrogen rates during the next 24 hours of operation. After this, the feed hydrocarbon and hydrogen rate was 2.2 cc / min (3.6 WHSV), but the hydrogen rate of 27 scc / min was maintained until the end of the run.
[0037]
The test results for the copper catalyst in Example 5 and Control Example 1 are shown in FIGS. FIG. 3 demonstrates the superior catalytic activity and stability of the catalyst disclosed in the present invention over the prior art. FIG. 5 demonstrates the superior butadiene yield of the present invention over the prior art. The yield of 1,3-butadiene in the same conversion of all alkynes over the catalyst disclosed in this invention is higher than that disclosed in the prior art. Example 5 also shows that if excess hydrogen is available after converting all acetylenic compounds in the feed stream, the excess hydrogen causes loss of 1,3-butadiene due to excessive hydrogenation. Suggest that excess hydrogen should be kept to a minimum in the selective hydrogenation zone.
[0038]
[Table 1]

[0039]
[Table 2]

[0040]
Example 6
The alumina used in Example 5 was calcined in air at 700 ° C. for 3 hours. A copper catalyst was prepared using the calcined alumina. 30 g Cu (NO in 128 ml deionized water) _Three ) _Two . 2.5H _Two O, Ni (NO _Three ) _Two . 6H _Two O, 0.047 g of AgNO _Three 0.396 g of Cr (NO _Three ) _Three . 9H _Two O and 0.396 g of Co (NO _Three ) _Two . 6H _Two A solution of O was made. 70 g of alumina was impregnated with the above solution using a rotary evaporator. The impregnated product was further dried in a vacuum oven at 110 ° C. overnight before calcining in air at 400 ° C. in a muffle furnace for 3 hours. The ABD of the catalyst was 0.57 g / cc. 18 g of this catalyst were blended with 100 ml of 3 mm diameter glass spheres and charged into the same reactor as in Control Example 1. The catalyst was activated in the same manner as in Control Example 1.
[0041]
444 ppm by weight of methylacetylene, 825 ppm by weight of vinylacetylene and 634 ppm by weight of ethylacetylene, 55.36% by weight of 1,3-butadiene, 0.12% by weight of 1,2-butadiene, 6.39% by weight T-2-butene, 4.13 wt% c-2-butene, 16.84 wt% 1-butene, 12.38 wt% isobutene, 3.53 wt% n-butane, 0.97 % Isobutane by weight, as well as 0.09% by weight of the other mixture C _Four The stream was selectively hydrogenated to remove acetylenic impurities at 119 psig. In this example, the hydrocarbon and hydrogen rates were maintained at a constant rate of 3 cc / min for hydrocarbons and 27 scc / min for hydrogen. The test results for the copper catalyst in Example 6 and Control Example 1 are shown in FIGS. 4 and 5 along with the results obtained from Example 5.
[0042]
4 and 5 clearly demonstrate the superior performance of the copper catalyst disclosed in the present invention over the prior art.
[0043]
Example 7
In this example, the catalytic distillation column is mixed C _Four Used for selective hydrogenation of acetylenic impurities in the stream. A larger batch of catalyst was prepared using 240 grams of alumina in exactly the same manner as described in Example 5. The catalyst (99.88 grams) was charged into a catalytic distillation tower (1 inch diameter x 25 feet high). The height of the catalyst bed in the tower was 6 feet. 80 inches at the top and bottom of the catalyst bed were filled with a 1/4 inch saddle. The catalyst was activated in the same manner as described in Control Example 1, except that the gas flow was increased in proportion to the catalyst weight.
[0044]
Acetylene-type impurities in the same feed used in Example 6 were removed by performing a selective hydrogenation in a catalytic distillation mode. The hydrocarbon feed rate was 1.2 pounds / hour. The hydrogen rate was 1 scf / hr at the beginning of the run, but was changed to a higher rate during the run. Hydrocarbon and hydrogen feeds were supplied at a point below the saddle filler. FIG. 6 shows the results. At hydrogen rates above 3 scf / hr, virtually all of the ethylacetylene and vinylacetylene in the feed was removed. Almost complete recovery of 1,3-butadiene was obtained. As shown in FIG. 6, the catalyst was much more stable under the catalytic operation than in the fixed bed operation.
[0045]
Example 8
This experiment was performed to demonstrate the beneficial effects of incorporating zinc oxide in a copper catalyst disclosed in the present invention to improve the performance of the copper catalyst. The copper catalyst was prepared according to the same procedure used in Example 5. 22.6 g Cu (NO in 100 ml deionized water) _Three ) _Two . 2.5H _Two O, Ni (NO _Three ) _Two . 6H _Two O, 0.04 g of AgNO _Three , And 4.0 g of Zn (NO _Three ) _Two . 6H _Two A mixed solution of O was prepared. Using a rotary evaporator, 60 g of the same alumina as used in Example 5 was impregnated with the above solution. The impregnated product was further dried in a vacuum oven at 110 ° C. overnight before calcining in a muffle furnace at 400 ° C. for 3 hours. 18 g of this catalyst were blended with 100 ml of 3 mm diameter glass spheres and charged into the same reactor used in Control Example 1. Catalyst activation was performed in the same manner as described in Control Example 1.
[0046]
475 ppm of methyl acetylene, 959 ppm by weight of vinyl acetylene and 731 ppm by weight of ethyl acetylene, 54.87% by weight of 1,3-butadiene, 0.12% by weight of 1,2-butadiene, 6.42% by weight of t -2-butene, 4.16 wt% c-2-butene, 16.76 wt% 1-butene, 12.53 wt% isobutene, 3.56 wt% n-butane, 1.27 wt% Of isobutane, as well as 0.09% by weight of the other _Four The stream was selectively hydrogenated to remove acetylenic impurities therein. Selective hydrogenation was performed at a constant temperature of 147 ° F and 119 psig. A constant hydrocarbon and hydrogen feed rate of 3 ml / min (6.1 WHSV) and 27.1 scc / min were used throughout the run. The results of this run are summarized in FIGS. The beneficial effects of zinc oxide incorporated in the copper catalyst on catalytic performance are clearly demonstrated in this example.
[0047]
Example 9
This example demonstrates the utility of one of the preferred solvents disclosed in this invention, tetrahydrofuran (THF). The copper catalyst prepared in Example 5 (36 grams) was charged into the same reactor used in Control Example 1. Mixed C used in this example _Four The feed had the following composition: 20 ppm methylacetylene, 588 ppm vinylacetylene, 599 ppm ethylacetylene, 44.51 wt% 1,3-butadiene, 0.07 wt% 1,2-butadiene, 6.29% by weight of t-2-butene, 4.33% by weight of c-2-butene, 15.97% by weight of 1-butene, 18.04% by weight of isobutene, 9.36% by weight of n- Butane, 1.30% by weight isobutane, and 0.01% by weight others. After a running time of 176 hours, the reactor was _Two After flushing with gas, 147 ° F., 200 psig for 1 hour, then 157 ° F. for 5 hours, 10 cc / min THF, 66.9 scc / min H _Two The catalyst was washed with THF to remove the polymer deposited on the catalyst surface. Reactor is N _Two After flushing with gas, selective hydrogen was continued. A constant temperature (147 ° F.) and pressure (119 psig) were maintained throughout the run. Table 3 lists the run conditions during this experiment.
[0048]
The result of this experiment is shown in FIG. As shown in FIG. 9, leakage of acetylene-type impurities occurred with an operating time of 128 hours. However, after washing the catalyst with THF, the product obtained under the same conditions as in the case of the leak did not contain detectable amounts of acetylenic impurities.
[0049]
[Table 3]

[0050]
Therefore, THF is one of the preferred solvents for catalyst regeneration. THF is also one of the preferred solvents used to perform selective hydrogenation using a catalytic distillation column. When THF is used as a solvent in the CD selective hydrogenation, THF can be fed to the distillation column above the catalyst bed or it can be mixed with mixed C _Four The column can be fed with the feed stream. In these two cases, different conditions for tower operation will be required. In the latter case, the column will operate under total internal reflux conditions with respect to THF. In both cases, THF will be removed from the column as a bottom product and recycled to the column. However, a portion of the recycled THF stream will be purified in the separator before returning to the column to avoid accumulation of heavy components in the recycled stream.
[0051]
Example 10A
Mixed C used in Control Example 2 _Four The copper catalyst prepared in Example 5 was tested for the selective hydrogenation of acetylenic impurities (7132 ppm of total acetylenes) in the feed. 18 g of catalyst were blended with 100 ml of 3 mm diameter glass spheres and charged into the same reactor as in Control Example 1. The catalyst was activated in the same manner as in Control Example 1. Selective hydrogenation was performed at a constant temperature of 147 ° F and 119 psig. During the first 66.5 hours of operating time, the hydrocarbon and hydrogen feed rates were 2.9 ml / min (5.87 WHSV) and 45 scc / min, respectively, and then 1.4 ml / min (2. 83 WHSV) and 24.1 scc / min.
[0052]
Example 10B
A copper catalyst promoted with palladium was prepared according to the present invention. The alumina used in Example 5 was calcined in air at 900 ° C. for 3 hours. 28.7 g Cu (NO) in 110 ml deionized water _Three ) _Two . 2.5H _Two O, Ni (NO _Three ) _Two . 6H _Two O, 0.04 g of AgNO _Three , 0.34 g of Cr (NO _Three ) _Three . 9H _Two O and 0.34 g of Co (NO _Three ) _Two . 6H _Two A mixed solution was prepared by dissolving O. The above calcined alumina (60 g) was impregnated with this solution using a rotary evaporator. After further drying the impregnation product in a vacuum oven at 110 ° C. overnight, it was calcined in air in a muffle furnace at 400 ° C. for 3 hours. 5.469 grams of an aqueous palladium (II) nitrate solution (Aldrich 38,004-0); 10% by weight of Pd (NO _Three ) _Two ) Is sprayed onto the surface of a copper catalyst sphere (29.762 grams) using an atomizer, while the copper catalyst sphere rolls around on a flat surface and the sphere is uniformly coated with a palladium solution. Was. It is very important to generate a fine mist of the palladium salt solution. The product sprayed with the palladium solution was calcined in air at 250 ° C. for 2 hours. The ABD of the Cu / Pd catalyst was 0.52 g / cc. Analysis of this catalyst shows 8.20% Cu, 0.71% Pd, 0.20% Ni, 0.11% Cr, and 0.17% Ag.
[0053]
22 g of this catalyst were blended with 100 ml of 3 mm diameter glass spheres and charged into the same reactor used in Control Example 1. The catalyst was activated by the following procedure; (1) The reactor was charged with 100 cc / min N 2 _Two Heat to 230 ° F in a gas stream and (2) 200cc / min H _Two To N _Two In addition to the gas flow, hold at 230 ° F for 3 hours, (3) N _Two Stop gas, H _Two The gas flow was increased to 300 cc / min and (4) heated to a reactor temperature of 572 ° F and held at 572 ° F for 3 hours, then the reactor was cooled to 30 cc / min H _Two Cooled to 147 ° F in a gas stream.
[0054]
Acetylene-type impurities in the same feed used in Example 10A were removed by selective hydrogenation. Selective hydrogenation was performed at a constant temperature of 142 ° F. However, during the first 73 hours of operation, the hydrocarbon and hydrogen feed rates were 3.7 ml / min (6.1 WHSV) and 45 scc / min, respectively, at a reactor pressure of 119 psig, then 6 psig at 108 psig. .1 ml / min (10.1 WHSV) and 74.2 scc / min. After a running time of 145 hours, the catalyst was brought to 74.2 scc / min H at 100 ° C. and 108 psig. _Two Washed with benzene (10 ml / min) in a stream for 5 hours. The selective hydrogenation was continued for 24 hours under the same conditions as immediately before the benzene washing, but with benzene (0.6 ml / min) mixed C _Four The reactor was fed simultaneously with the feed. Then, for the next 18 hours, the feed rate was increased to 10 ml / min mixed C _Four Feed, 1 ml / min benzene, and 90 scc / min H _Two Changed to The feed rate was then increased to 15 ml / min mixing C at a reactor pressure of 95 psig for the next 30 hours. _Four Feed, 1.5 ml / min benzene, and 112 sccc / min H _Two Increased. After this, the selective hydrogenation was carried out for 24 hours, reducing the hydrogen rate to 95 scc / min, while keeping the other process parameters under the same conditions. The feed rate was then increased to 10 ml / min mixed C for the next 66 hours. _Four Feed, 1 ml / min benzene, and 54 scc / min H _Two , While keeping the other process parameters at the same conditions.
[0055]
The results of Examples 10A and 10B, along with Control Example 2, are shown in FIGS. As shown in FIG. 8, the copper catalyst that was not promoted with palladium had very low activity in handling high concentrations of acetylenic impurities. However, when the copper catalyst was promoted with palladium in the procedure disclosed in the present invention, the catalytic activity was dramatically improved. Surprisingly, the present palladium-promoted copper catalyst has much better activity than commercial Pd-selective hydrogenation catalysts. Even more surprisingly, the palladium promoted catalyst also has superior 1,3-butadiene yields over commercial palladium catalysts at the same conversion of acetylenes, despite its much higher activity. Also, the deactivation rate of the present palladium promoted catalyst was much better than commercial Pd catalyst or unpromoted copper catalyst. This example clearly demonstrates the superior performance of the present palladium promoted copper catalyst over palladium or unpromoted copper catalysts for selective hydrogenation of high acetylenic feeds.
[0056]
Example 11
Gamma alumina (obtained from UCI, 1/8 inch extrudate, surface area about 260 m ^Two / g) into 10-20 mesh granules. According to the alumina supplier, the source of the alumina was the same as the alumina used in Control Example 1. However, this granular alumina has a lower ABD (0.50 g / cc) than the alumina used in Control Example 1 (0.792 g / cc ABD). 30 g Cu (NO in 128 ml deionized water) _Three ) _Two . 6H _Two O, 0.93 g Ni (NO _Three ) _Two . 6H _Two O, 0.047 g of AgNO _Three , 0.396Cr (NO) _Three . 9H _Two O and 0.396Co (NO _Three ) _Two . 6H _Two A solution of O was made. 70 g of granular alumina was impregnated with the above solution using a rotary evaporator. The impregnated product was dried in a vacuum oven at 110 ° C. overnight and then calcined in a muffle furnace at 400 ° C. for 3 hours. 18 g of this catalyst were blended with 110 ml of 3 mm diameter glass spheres and charged into the same reactor as in Control Example 1. The catalyst was activated by the following procedure; (1) The reactor was charged with 100 cc / min N 2 _Two Heat to 230 ° F in a gas stream and (2) 200cc / min H _Two To N _Two In addition to the gas flow, then hold at 230 ° F. for 3 hours; _Two Stop gas, H _Two The gas flow was increased to 300 cc / min and (4) heated to a reactor temperature of 662 ° F. and held at 662 ° F. for 3 hours, then the reactor was cooled to 30 cc / min H2. _Two Cooled to 147 ° F in a gas stream.
[0057]
The same feed used in Control Example 1 was selectively hydrogenated to remove acetylenic impurities at a pressure of 119 psig. During the first 29 hours of operation, the feed hydrocarbon and hydrogen rates were 1.8 cc / min (3.6 WHSV) and 25.7 sc./min, respectively. The feed rate was then increased to 2.4 cc / min (4.9 WHSV) for hydrocarbons and 34.3 sc./min for hydrogen rates during the next 24 hours of operation. Thereafter, until the end of the run, the feed rate was further increased to 3 cc / min (6.1 WHSV) for hydrocarbons, but the hydrogen feed rate was reduced to 30 sc./min.
[0058]
A comparison of the test results of this experiment with those of Control Examples 1 and 4 is shown in FIGS. 12 and 13 to demonstrate the effect of the ABD of the supported alumina on catalytic performance. The catalyst prepared using the lower ABD alumina in this example (meaning higher porosity) was superior to the higher ABD alumina used in Control Examples 1 and 4. The alumina in this example and control example 1 were made from the same raw materials. However, the lower ABD alumina used in this example results in a more effective catalyst in removing acetylenic impurities. The catalyst in this example has a better 1,3-butadiene yield than in Control Example 1. The alumina used to make the catalyst in Control Example 4 has a surface area that falls within the preferred range of surface areas disclosed in the present invention. However, the ABD of the alumina in Control Example 4 was 0.98 g / cc, the preferred ABD disclosed in the present invention (<0.65 g / cm ^Three Higher). The effectiveness of the catalyst in Control Example 4 in removing acetylenic impurities falls roughly between Control Examples 1 and 11. There is almost no difference in the yield of 1,3-butadiene between Example 11 and Control Example 4.
[0059]
Example 12
This example was performed to demonstrate the superior performance of a palladium promoted copper catalyst for the selective hydrogenation of a feed containing a relatively high concentration of acetylenic impurities.
[0060]
A copper catalyst promoted with palladium was prepared according to the present invention. The alumina used in Example 5 was calcined in air at 900 ° C. for 3 hours. 4.61 g of 10% by weight Pd in 10% by weight nitric acid (NO _Three ) _Two Solution (Aldrich 38,004-0: 10 wt% Pd (NO _Three ) _Two ) Was diluted with 6.378 g of deionized water to prepare 1.866 g of Cu (NO _Three ) _Two 2.5H _Two A mixed solution was prepared by dissolving O. 5.56 g of this mixed solution is sprayed onto a 30 g calcined alumina sphere surface using an atomizer, while the alumina spheres roll around on a flat surface and then the sprayed product is Dry in a vacuum oven at 115 ° C. The dried product was calcined at 250 ° C. for 2 hours in air.
[0061]
18 g of this catalyst were mixed with 110 ml of 3 mm diameter glass spheres and charged into the same reactor used in Control Example 1. The catalyst was activated in the same manner as described in Example 11. Acetylene-type compounds in the same feed used in Control Example 3 were removed by performing a selective hydrogenation. Selective hydrogenation was performed at a constant temperature of 142 ° F and 108 psig. The hydrocarbon feed rate was maintained at 10 ml / min (20.2 WHSV) until the end of the run. However, variations in the hydrogen flow rate in the range of 44 scc / min to 90 scc / min occurred during the run.
[0062]
The results of Example 12 and Control Example 3 are shown in FIGS. The superior catalytic activity of the present palladium promoted copper catalyst over conventional palladium catalysts is clearly demonstrated. Although the feed rate in Example 12 is at least four times higher than that of Control Example 3, the present palladium promoted copper catalyst has a superior 1,3-butadiene advantage over the conventional palladium catalyst of Control Example 3. Less than 20 ppm C while having a yield (expressed as recovery in FIG. 14) _Four Products containing acetylenes can be produced. C _Four 100% recovery of acetylenes vs. C _Four Defined by% conversion of acetylenes. For example, C _Four The 0% recovery of acetylenes is C _Four Equivalent to 100% removal of acetylenes and 100% 1,3-butadiene recovery is equivalent to 0% conversion of 1,3-butadiene.
[0063]
The ratio of ethyl acetylene to vinyl acetylene in the product is shown in FIG. The palladium promoted copper catalyst is much more reactive to vinyl acetylene than conventional palladium catalysts. The present palladium promoted copper catalyst has about an order of magnitude higher activity than the unpromoted copper catalyst. It is unexpected that the present palladium-promoted copper catalyst has several times higher activity than conventional Pd catalysts and yet has excellent selectivity for retaining 1,3-butadiene.
[Brief description of the drawings]
[0064]
FIG. 1 is a schematic diagram of a CD reactor having the present copper catalyst on top for selective hydrogenation of acetylenes.
FIG. 2 is a schematic diagram of a CD reactor having the present copper catalyst at the top for selective hydrogenation of acetylenes and a Group VIII catalyst at the bottom for reacting mercaptans and diolefins.
FIG. 3 is a graph showing a pore distribution of an alumina carrier and a catalyst of Example 5.
FIG. 4 is a graphical representation of all product alkynes in the products of Example Control 1, Example 5 and Example 6.
FIG. 5 is a graph of the yield of all 1,3-butadiene products of Example Control 1, Example 5 and Example 6.
FIG. 6 is a graph showing the results of Example 7 on a CD.
FIG. 7 is a graphical representation of all alkynes in the products of Example 5 (non-CD) and Example 8 (CD).
FIG. 8 is a graph comparing the 1,3-butadiene product of Example 5 (non-CD) and Example 8 (CD).
FIG. 9 is a graphical illustration of the benefits of solvent treatment of the catalyst used.
FIG. 10 is a graph comparing Examples 10A and 10B to show the benefits of Pd promoted Cu.
FIG. 11 is a graph comparing Examples 10A and 10B to show the benefit of Pd promoted Cu on 1,3-butadiene production.
FIG. 12 is a graphical illustration of the benefits of ABDs according to the present invention in the case of acetylene removal, comparing Control Examples 1 and 4 and Example 11.
FIG. 13 is a graphical illustration of the benefits of an ABD according to the invention for a 1,3-butadiene product, comparing Control Examples 1 and 4 and Example 11.
FIG. 14 is a graphical illustration of the benefits of the present palladium promoted copper catalyst, comparing Example 12 with Control Example 3.
FIG. 15 is a graphical illustration of a chemical fingerprint distinguishing the present palladium promoted copper catalyst from a conventional palladium catalyst by comparing Example 12 with Control Example 3.

Claims (18)

A copper component and at least one Group VIII metal component on an alumina support that includes at least one of the following properties: an average pore diameter greater than 200 Å or an apparent bulk density of less than about 0.70 g / cm ³ ; A catalyst for the selective hydrogenation of acetylenes, comprising an Ag, Au component or a component of a mixture thereof. The catalyst according to claim 1, comprising an Ag, Au component or a component of a mixture thereof. The catalyst of claim 1, comprising at least one Group VIII metal component. The catalyst of claim 1, comprising at least one Group VIII metal component and components of Ag, Au or a mixture thereof. The catalyst of claim 1, comprising at least one Group VIII metal component, Ag component and Au component. The catalyst of claim 2, 3, 4 or 5, wherein the Group VIII component comprises Pd. The catalyst according to claim 2, 3, 4 or 5, comprising a Zn component. The catalyst of claim 1, comprising an alumina support having an average pore diameter of greater than 200 Angstroms. Containing alumina support having a bulk density of about 0.70 g / cm ³ less than the apparent catalyst according to claim 1. A catalyst for the selective hydrogenation of acetylenes, comprising a copper component, at least one Group VIII metal component and a Zn component. 11. The catalyst according to claim 10, comprising components of Ag, Au or a mixture thereof. 11. The catalyst of claim 10, comprising about 0.1 to 25% by weight Cu. 2. Selective hydrogenation of acetylenes comprising contacting a feed comprising acetylenes at least partially in the liquid phase with a catalyst of claim 1 under conditions that selectively hydrogenate the acetylenes. Method. The soluble polymer continuously deposits on the catalyst during the hydrogenation, resulting in reduced activity of the catalyst for selective hydrogenation of acetylenes, the hydrogenation being interrupted intermittently, 14. The method of claim 13, wherein a solvent of a soluble polymer contacts the catalyst to remove a portion of the polymer and restore a portion of the activity of the catalyst for the selective hydrogenation. The method according to claim 14, wherein the solvent comprises at least one of tetrahydrofuran, furan, 1,4-dioxane, ethers, gamma-butyrolactone, benzene or toluene. 11. Selective hydrogenation of acetylenes comprising contacting a feed comprising at least partially acetylenes in a liquid phase with the catalyst of claim 10 under conditions that selectively hydrogenate the acetylenes. Method. The soluble polymer continuously deposits on the catalyst during the hydrogenation, resulting in reduced activity of the catalyst for selective hydrogenation of acetylenes, the hydrogenation being interrupted intermittently, 17. The method of claim 16, wherein a solvent of a soluble polymer contacts the catalyst to remove a portion of the polymer and restore a portion of the activity of the catalyst for the selective hydrogenation. 18. The method of claim 17, wherein the solvent comprises at least one of tetrahydrofuran, furan, 1,4-dioxane, ethers, gamma-butyrolactone, benzene, or toluene.

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